In general, small electronic devices, for example electronic medical devices that can be worn or implanted in a person, can benefit significantly in some applications from reductions in size and/or power consumption. However, reducing size and/or power consumption may be challenging because relatively large and high power components are needed to achieve the high sensitivity and selectivity when processing signals in body worn electronics. Accordingly, known body worn electronic devices are not capable of achieving desirable sensitivity and selectivity for processing of bio-signals while being sufficiently small and low-power.